Working collaboratively with Git

Parisa Gregg

Welcome

Slides

Who am I?

Jumping Rivers

  • Data science
    • Python/ R, machine learning, dashboards, API’s
  • Data engineering
    • Data pipelines, server health and security, managed RStudio (Posit) services
  • Training
    • Python, R, Git + many more

Outline

  1. Common issues faced
  2. Some solutions
  3. How can Version Control Systems help?
  4. Demo: Intro to GitHub

Common issues

Tracking versions

Any of these file names look familiar?

code_v1.R
code_v1b_add_plot.R
code_v1b_add_plot_FINAL.R
code_v1b_add_plot_FINAL_FINALv2_sept2020.R
code_v1b_add_plot_FINAL_FINALv2_sept2020_Maria_edits.R

Collaborating

  • Multiple people making edits to the same file
  • Everyone has their own version
  • Duplicated work

Backing up & sharing work

How to combat these issues?

  • Have a system

  • Best practices

    • Keep changes small
    • Share changes frequently
    • Back-up everything

Manual Versioning

  • Standardized naming convention

    • 0.1-ptg-exciting-report.txt

    • 0.2-ptg-exciting-report.txt

    • 1.0-ptg-exciting-report.txt (finalised version)

    • 1.1-ptg-exciting-report.txt (revision)

Manual versioning

  • Structured folder of copies
<project-name>
|   CHANGELOG.txt
└───current
│   │   code.R
|   |   report.txt
└───2023-06-13
|   |   code.R
|   |   report.txt
└───2023-06-12
|   |   code.R
|   |   report.txt

Beyond manual versioning

  • Versioning manually requires a lot of self-discipline

  • Combining versions manually is hard work

  • Might need a version control system such as Git

Git

What is Git?

  • Widely used Version Control System

  • Automatically tracks changes in your project

  • Changes by multiple people can be combined into a single file

  • Backups stored securely & remotely

What are GitHub and GitLab?

  • Think about e-mail… we could host our own e-mail server, but that’s usually too much effort

  • Git is like e-mail

  • GitLab & GitHub are like gmail or yahoo

  • There are other git hosting services

  • Today we’ll focus on GitHub

Demo: Getting started with GitHub

Setting up a GitHub account

Authentication

  • GitHub uses personal access tokens (PATs) as a secure method of authentication

  • A PAT is an auto-generated strong passphrase (not ‘monkey123’!)

  • The user can set an automatic expiry date and different permissions for each token

  • This guide explains how to set one up in GitHub (make sure to select ‘repo’ when setting the scopes)

Creating a Git repository (project)

There are a couple of different ways that we can start using a Git repository:

  • Clone an existing repository
  • Create a new repository from scratch

Cloning a GitHub repository

  • Downloads a copy of that repository to your machine

  • Takes the latest snapshot available (all of the files) from GitHub

  • By default saved in a folder with the same name as the repository

Cloning a GitHub repository

Commits

  • Usually when working you would save your files

  • In Git, instead of just saving, we save and commit

  • Commit takes a snapshot of all your files

Staging area

  • Not all changes are included in a commit

  • Add files to the staging area before committing

Making changes locally

We are going to:

  • Edit & save some files in our working directory

  • Add these changes to the staging area

  • Commit the changes in the staging area to our local repository

Making changes locally

Workflow

Updating the remote

Updating the remote

Now we are going to:

  • Check for changes by any colleagues by pulling
  • Push our local changes to the remote repository

So to recap

Not just version control!

  • Project management

    • Issues
    • Labels
    • Milestones

  • Continuous Integration

  • Automated deployments

  • Security